感应电机定子温度监测的一种新方法

定子绕组温度监测是电机安全运行的重要保障。文中比较了两种温度监测方法，提出了一种新的定子电阻估计方法，从而可以直接得到电机定子绕组的温度。感应电机稳态运行时，具有转子磁铁与电流矢量正交的特性。而由于定子电阻估计误差的存在，使得电压型磁铁观测器得到的磁铁与电流并不正交，由此可推导出实际的定子电阻。由于定子电阻直接反映其绕组温度，适用于各种运行工况，因此文中提出的定子温度监测方法可以作为电机过热保护的一种辅助措施。

A NEW METHOD FOR STATOR TEMPERATURE MONITORING FOR INDUCTION MOTOR

Temperature monitoring is one of the fundamental protections required for induction motors. After comparing two temperature monitoring methods, a new stator resistance estimation method for stator winding temperature monitoring is presented. Because the stator resistance is a direct indicator of stator winding temperature responding to all of the situations, the accurate estimation of it is critical for this approach. The perpendicular relationship of rotor flux vector and rotor current vector in steady state will not hold if the stator resistance in voltage model flux observer has error. The resistance could be tuned to actual value by ensuring the perpendicular relationship. The proposed method could be a supplementary protection of thermal protection of induction motor.